Multi-way emptying ejector system

Abstract

Multi-way emptying system for a power machine (112) comprising the following: an ejector (140) which includes a restriction, a first (142) and a second inlet (144) and an outlet (146); and a shut-off valve (214) which is fixedly attached to an inlet (23) of the power machine (112) and coupled to the outlet (146), wherein the shut-off valve (214) is configured to close in response to a separation of the shut-off valve (214) from the inlet (23) of the power machine (112).

Description

[0001] An ejector or Venturi nozzle can be used as a vacuum source in two-way venting systems in an engine for fuel vapor recovery. For example, an ejector inlet can be connected upstream of a compressor to an engine inlet via a hose or line, while an ejector outlet can be connected downstream of the compressor to an engine inlet via a hose or other line. The fluid moving through the ejector provides a vacuum at an ejector suction inlet, which can be connected to a fuel vapor canister, to assist in emptying the fuel vapor canister during supercharged operation.

[0002] In some examples, the moving fluid may contain fuel vapors, untreated engine emissions, and / or engine crankcase vapors. If the ejector develops a leak, or if one or more hoses or lines connected to the ejector deteriorate, the gases may escape into the atmosphere. Leaks may become apparent at the ejector inlets or outlet, for example, if the ejector is subjected to stress, causing a break or deterioration in the ejector assembly. Alternatively, leaks may become apparent if the hoses, lines, or pipes connected to the ejector inlets or outlet deteriorate, break, or become disconnected from the ejector.

[0003] Some approaches diagnose and detect leaks in ejector system components adjacent to and / or upstream of the ejector inlets. For example, using various sensors in a power machine system, leaks in hoses, pipes, or piping coupled to the ejector inlet or to other locations upstream of the ejector outlet in an ejector system can be detected. However, such approaches fail to diagnose or detect leaks in an ejector system at or downstream of the ejector outlet. For instance, a hose or other pipe might be used to couple the outlet of an ejector located upstream of a compressor to a power machine inlet.If such a hose deteriorates or becomes decoupled from the ejector outlet, the resulting leak in the ejector system may go undetected, leading to increased emissions and a deterioration of engine operation.

[0004] JP 2009-180 095 A discloses a device for generating a vacuum. DE 10 2014 100 401 A1 discloses a multi-way emptying ejector system. US 5 005 550 A discloses a fuel vapor purging system for a vehicle vapor storage tank.

[0005] The inventors recognized the aforementioned disadvantages and developed a two-way discharge system for a power machine. According to the invention, a multi-way discharge system, such as a two-way system, for a power machine comprises the following: an ejector with a restriction, a first and a second inlet and an outlet, and a shut-off valve that is fixedly attached to an inlet of the power machine and coupled to the outlet. The shut-off valve can, for example, be configured to close in response to a disconnection from the inlet of the power machine.

[0006] In this way, the shut-off valve coupled to the ejector outlet can be closed in response to a detected leak or other deterioration in the multi-way drain system, thereby reducing unwanted emissions due to leaks in a pipe connecting the ejector outlet to the engine inlet. For example, in response to a detected disconnection between the shut-off valve and the engine inlet, operation of the fuel evaporation system can be interrupted, and corrective action can be taken to reduce unwanted emissions. Specifically, this approach can reduce the need to monitor all sections of a drain system to diagnose leaks. Furthermore, this approach can reduce the number of sensors required to monitor a drain system for leaks.Furthermore, leaks in the draining system can be detected without adding any additional sensors to the vehicle system.

[0007] The advantages mentioned above, as well as other advantages and features of the present description, will be readily apparent from the detailed description that follows, whether considered alone or in conjunction with the accompanying drawings. It should be understood that the above summary is provided to introduce, in simplified form, a selection of the concepts that will be further described in the detailed description below. It is not intended to identify key or essential features of the claimed subject matter, the scope of which is clearly defined by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to those implementations that eliminate all the disadvantages mentioned above or in any part of the disclosure. Fig. 1 and Fig. Figure 2 shows schematic graphical representations of exemplary vehicle systems with two-way emptying ejector systems. Fig. Figure 3 shows an example procedure for a two-way emptying system according to the disclosure.

[0008] This description relates to the diagnosis of leaks in a two-way drainage system with an ejector in a vehicle, such as the exemplary vehicle systems described in the Fig. 1 and Fig. 2 are shown. As described above, leaks, e.g., leaks due to stress on the ejector and / or deterioration in the ejector system components, such as the hoses or lines, can be diagnosed and detected in the system components at or upstream of the inlets to the ejector. To diagnose and take corrective action in response to leaks downstream of an ejector outlet, e.g., between the ejector and an air intake system (LES), a shut-off valve can be attached directly to the LES and coupled to the ejector outlet. As shown in Fig. As shown in Figure 3, the shut-off valve can be closed to reduce unwanted emissions if a separation between the shut-off valve and the air intake system is detected. Furthermore, leaks at locations in the ejector system upstream of the ejector outlet can be diagnosed, and corrective action can be taken in response to a detected leak.

[0009] The figures show Fig. Figure 1 shows a schematic representation of a vehicle system 100. The vehicle system 100 comprises a power engine system 102, which is coupled to a fuel vapor recovery system 200, and a fuel system 106. The power engine system 102 can include a power engine 112, which has several cylinders 108. The power engine 112 comprises a power engine inlet 23 and a power engine outlet 25. The power engine inlet 23 comprises a throttle valve 114, which is fluidically coupled to the intake manifold 116 of the power engine via an intake channel 118. An air filter 174 is positioned upstream of the throttle valve 114 in the intake channel 118. The power engine outlet 25 comprises an exhaust manifold 120, which leads to an exhaust port 122, which directs the exhaust gas to the atmosphere. The engine outlet 122 can contain one or more exhaust gas purification devices 124, which may be mounted in a closely coupled position in the outlet.One or more exhaust aftertreatment devices may include a three-way catalytic converter, a lean NOx trap, a diesel particulate filter, an oxidation catalyst, etc. It is recognized that other components may be included in the vehicle system, such as various valves and sensors, as further elaborated below.

[0010] The throttle valve 114 can be located in the inlet duct 118 downstream of a compressor 126 of a charging device, such as a turbocharger 50 or a supercharger. The compressor 126 of the turbocharger 50 can be located between the air filter 174 and the throttle valve 114 in the inlet duct 118. The compressor 126 can be driven, at least partially, by the exhaust turbine 54, which is located in the exhaust duct 122 between the exhaust manifold 120 and the exhaust aftertreatment device 124. The compressor 126 can be coupled to the exhaust turbine 54 via a shaft 56. The compressor 126 can be configured to draw in intake air at atmospheric pressure into an air intake system (LES) 173 and supercharge it to a higher pressure. Supercharged engine operation can be performed using the supercharged intake air.

[0011] The amount of boost can be controlled, at least in part, by controlling the quantity of exhaust gas directed through the exhaust turbine 54. For example, if a greater amount of boost is requested, a larger quantity of exhaust gas can be directed through the turbine. Conversely, if, for example, a smaller amount of boost is requested, some or all of the exhaust gas can bypass the turbine via a turbine bypass channel, as controlled by a boost pressure control valve (not shown). The amount of boost can also be controlled, additionally or optionally, by controlling the quantity of intake air directed through the compressor 126. The controller 166 can adjust the quantity of intake air drawn through the compressor 126 by adjusting the position of a compressor bypass valve (not shown).In one example, if a larger amount of boost is required, a smaller amount of intake air can be routed through the compressor bypass duct.

[0012] The fuel system 106 can include a fuel tank 128 coupled to a fuel pump system 130. The fuel pump system 130 can include one or more pumps to pressurize the fuel supplied to the fuel injectors 132 of the engine 112. While only a single fuel injector 132 is shown, additional fuel injectors can be provided for each cylinder. The engine 112 can, for example, be a direct-injection gasoline engine, with additional injectors provided for each cylinder. It is recognized that the fuel system 106 can be a non-recirculating fuel system, a recirculating fuel system, or various other types of fuel system. In some examples, a fuel pump can be configured to draw the fuel from the bottom of the tank.The vapors generated in the fuel system 106 can be directed via a line 134 to a fuel vapor recovery system 200, which is described in more detail below, before being discharged to the engine inlet 23.

[0013] The fuel vapor recovery system 200 includes a fuel vapor retention device, shown here as a fuel vapor canister 104. The canister 104 can be filled with an adsorbent capable of binding large quantities of vaporized hydrocarbons. In one example, the adsorbent used is activated carbon. The canister 104 can receive the fuel vapors from the fuel tank 128 through the line 134. While the illustrated example shows a single canister, it is recognized that in alternative embodiments, several such canisters can be connected together. The canister 104 can be connected to the atmosphere through a vent 136. In some examples, a canister vent valve 172 can be located along the vent 136, coupled between the fuel vapor canister and the atmosphere, and can regulate the flow of air and vapors between the canister 104 and the atmosphere.In other examples, however, a canister vent valve may not be included. In one example, the operation of the canister vent valve 172 may be controlled by a canister vent solenoid (not shown). Based on whether the canister is to be emptied or not, the canister vent valve may, for example, be open or closed. In some examples, an evaporative leak detection module (ELCM) may be located in the vent opening 136, and it may be configured to control venting and / or assist in leak detection.

[0014] Line 134 may optionally include a fuel tank isolation valve (not shown). Among other functions, the fuel tank isolation valve allows the fuel vapor canister 104 to be maintained at low pressure or a vacuum without increasing the rate of fuel evaporation from the tank (which would otherwise occur if the fuel tank pressure were reduced). The fuel tank 128 may contain multiple fuel mixtures, including fuels with a range of alcohol concentrations, such as various gasoline-ethanol blends, including E10, E85, gasoline, etc., and combinations thereof.

[0015] The fuel vapor recovery system 200 can include a two-way drain system 171. The drain system 171 is coupled to the canister 104 via a line 150. The line 150 can contain a canister drain valve (CPV) 158. Specifically, the CPV 158 can control the flow of vapors along the line 150. The quantity and rate of vapors discharged by the CPV 158 can be determined by the duty cycle of an associated CPV solenoid 202. For example, the duty cycle of the CPV solenoid can be determined by the controller 166 in response to the operating conditions of the engine, including, for example, an air-fuel ratio. By commanding the CPV to close, the controller can seal the fuel vapor canister from the fuel vapor discharge system, preventing any vapors from being discharged through the fuel vapor discharge system.By commanding the CPV to open, the controller can, unlike the fuel vapor discharge system, allow the vapors to be discharged from the fuel vapor canister.

[0016] The fuel vapor canister 104 operates to store vaporized hydrocarbons (HCs) from the fuel system 106. Under certain operating conditions, such as during refueling, fuel vapors present in the fuel tank can be displaced when liquid is added. The displaced air and / or vapors can be routed from the fuel tank 128 to the fuel vapor canister 104 and then through the vent 136 to the atmosphere. In this way, an increased quantity of vaporized HCs can be stored in the fuel vapor canister 104. During subsequent engine operation, the stored vapors can be vented back into the incoming air charge via the fuel vapor discharge system 200.

[0017] Line 150 is coupled to an ejector 140 in an ejector system 141 and contains a check valve 170, which is arranged therein between the ejector 140 and the CPV 158. The check valve 170 can prevent the intake air from flowing from the ejector into line 150, while allowing the flow of fluid and fuel vapors from line 150 into the ejector 140.

[0018] A line 151 connects line 150 to inlet 23 at one point within line 150 between check valve 170 and CPV 158, and at another point in inlet 23 downstream of throttle valve 114. Line 151 can be used, for example, to direct fuel from canister 104 to inlet 23 during a draining event, utilizing the vacuum generated in inlet manifold 116. Line 151 may include a check valve 153. The check valve 153 can prevent intake air from flowing from inlet manifold 116 into line 150, while allowing fluid and fuel vapors to flow from line 150 through line 151 into inlet manifold 116 during a canister draining event.

[0019] Line 148 can be coupled to ejector 140 at a first port or inlet 142. Ejector 140 includes a second port 144 or inlet that couples ejector 104 to line 150. Ejector 140 is positioned upstream of throttle valve 114 and downstream of compressor 126 and is coupled to inlet 23 via line 148. During supercharged operation, line 148 can direct compressed air in inlet line 118 downstream of compressor 126 into ejector 140 via port 142.

[0020] The ejector 140 can also be coupled to the inlet line 118 via a shut-off valve 214 in a position upstream of the compressor 126. The shut-off valve 214 is fixedly attached to the air inlet system 173 along the line 118 at a location between the air filter 174 and the compressor 126. For example, the shut-off valve 214 can be coupled to an existing LES nipple or to another opening, such as an existing SAE quick-connect fitting, in the LES 173. The fixed attachment can involve an inflexible direct connection. For example, an inflexible fixed connection could be achieved by a variety of methods, including rotary welding, laser bonding, or adhesive bonding. The shut-off valve is coupled to a third port 146 or outlet of the ejector 140. The shut-off valve 214 is configured to close in response to leaks detected downstream of the outlet 146 of the ejector 140.As in . Fig. As shown in Figure 1, in some examples a line or hose 152 can couple the third port 146 or outlet of the ejector 140 to the shut-off valve 214. In this example, the shut-off valve 214 can close, thus interrupting airflow from the engine inlet downstream of the compressor through the converging orifice in the ejector, when a separation of the shut-off valve 214 from the LES 173 is detected. As shown below with reference to Fig. As described in 2, in other examples the shut-off valve can be integrated with the ejector 140 and directly coupled to it.

[0021] The ejector 140 includes a housing 168 coupled to ports 146, 144, and 142. In one example, only the three ports 146, 144, and 142 are included in the ejector 140. The ejector 140 may include various check valves arranged within it. In some examples, the ejector 140 may include, for instance, a check valve positioned adjacent to each port in the ejector 140, such that a unidirectional flow of fluid or air is present at each port. The air from the inlet line 118 downstream of the compressor 126 may, for example, be drawn through the ejector 140. B. via the inlet port 142 into the ejector 140 and can flow through the ejector and exit the ejector at the outlet port 146 before being directed into the inlet line 118 in a position upstream of the compressor 126.This airflow through the ejector can generate a negative pressure at the inlet port 144 due to the Venturi effect, so that a negative pressure is provided across port 144 of line 150 during charged operating conditions. In particular, a low-pressure area is created adjacent to the inlet port 144, which can be used to draw venting vapors from the canister into the ejector 140.

[0022] The ejector 140 includes a nozzle 204 with an opening that converges in one direction from the inlet 142 to the suction inlet 144, so that when air flows through the ejector 140 in one direction from port 142 to port 146, a vacuum is created at port 144 due to the Venturi effect. This vacuum can be used to assist fuel vapor venting under certain conditions, such as during supercharged operation of the engine. In one example, the ejector 140 is a passive component. That is, the ejector 140 is designed to provide a vacuum to the fuel vapor venting system via line 150 to assist venting under various conditions without being actively controlled.

[0023] While the CPV 158 and the throttle valve 114 can be controlled via the controller 166, the ejector 140, for example, can be neither controlled via the controller 166 nor subject to any other active control. In another example, the ejector with variable geometry can be actively controlled to adjust the amount of vacuum supplied by the ejector to the fuel vapor recovery system via line 150.

[0024] During selected operating conditions of the engine and / or vehicle, such as after a start-up temperature of an exhaust aftertreatment device has been reached (e.g., a threshold temperature has been reached after warming up from ambient temperature), and with the engine running, the controller 166 can set the duty cycle of a (not shown) canister vent valve solenoid and open or keep open the canister vent valve 172. The canister vent valve 172 can remain open, for example, except during the vacuum tests performed on the system. Simultaneously, the controller 12 can set the duty cycle of the CPV solenoid 202 and open the CPV 158. The pressures within the fuel vapor discharge system 200 can then draw fresh air through the vent 136, the fuel vapor canister 104 and the CPV 158, so that the fuel vapors flow into the line 150.

[0025] The operation of ejector 140 within the fuel vapor discharge system 200 under vacuum conditions is now described. These vacuum conditions can include the vacuum conditions of the intake manifold. The vacuum conditions of the intake manifold can be present, for example, during an engine idle, where the manifold pressure is a threshold value below atmospheric pressure. This vacuum in the intake system 23 can draw fuel vapor from the canister through lines 150 and 151 into the intake manifold 116. Furthermore, at least a portion of the fuel vapor can flow from line 150 through port 144 into ejector 140. Upon entering the ejector through port 144, the fuel vapor can flow through nozzle 204 to port 142. Specifically, the vacuum of the intake manifold causes the fuel vapor to flow through opening 212.Because the diameter of the area inside the nozzle gradually increases in one direction from port 144 to port 142, the fuel vapors flowing through the nozzle in this direction diffuse, increasing the pressure of the fuel vapors. After passing through the nozzle, the fuel vapors exit the ejector 140 through the first port 142 and flow through the line 148 to the intake port 118 and then to the intake manifold 116.

[0026] Next, the operation of the ejector 140 within the fuel vapor discharge system 200 during the charging conditions is described. The charging conditions may include conditions during which the compressor is in operation. For example, the charging conditions may include a high engine load condition and / or a super-atmospheric inlet condition, where the inlet manifold pressure is greater than atmospheric pressure by a threshold amount.

[0027] Fresh air enters the intake duct 118 at the air filter 174. During charging, the compressor 126 pressurizes the air in the intake duct 118, resulting in a positive intake manifold pressure. The pressure in the intake duct 118 upstream of the compressor 126 is lower than the intake manifold pressure during compressor 126 operation. This pressure differential causes fluid to flow from the intake duct 118 through the duct 148 and via the ejector inlet 142 into the ejector 140. This fluid may, for example, contain a mixture of air and fuel. After the fluid has flowed into the ejector via port 142, it flows through the converging opening 212 in the nozzle 204 in one direction from port 142 to outlet 146. Because the diameter of the nozzle gradually decreases in one direction of this flow, a low-pressure zone is created in a region of opening 212 adjacent to the suction inlet 144.The pressure in this low-pressure zone can be lower than the pressure in line 150. If this pressure differential is present, it provides a vacuum at line 150 to draw fuel vapor from canister 104. This pressure differential can further cause a flow of fuel vapor from the fuel vapor canister through the CPV and into port 144 of ejector 140. Upon entering the ejector, the fuel vapor, along with the fluid from the inlet manifold, can be drawn out of the ejector via outlet port 146 and into inlet 118 at a position upstream of compressor 126. The operation of compressor 126 then draws the fluid and fuel vapor from ejector 140 into inlet 118 and through the compressor.After the fluid and fuel vapors have been compressed by the compressor 126, they flow through the charge air cooler 156 for supply via the throttle valve 114 to the intake manifold 116.

[0028] The vehicle system 100 can further include a control system 160. It is shown that the control system 160 receives information from several sensors 162 (various examples of which are described here) and sends control signals to several actuators 164 (various examples of which are described here). As an example, the sensors 162 can include an exhaust gas sensor 125 (located in the exhaust manifold 120) and various temperature and / or pressure sensors arranged in the intake system 23. For example, a pressure or airflow sensor 115 in the intake line 118 downstream of the throttle valve 114, a pressure or airflow sensor 117 in the intake line 118 between the compressor 126 and the throttle valve 114, and a pressure or airflow sensor 119 in the intake line 118 upstream of the compressor 126. Other sensors, such as...Additional pressure, temperature, air / fuel ratio, and composition sensors can be connected to various locations within the vehicle system 100. As another example, the actuators 164 can include fuel injectors 132, a throttle valve 114, a compressor 126, a fuel pump of the pumping system 130, etc. The control system 160 can include an electronic controller 166. The controller can receive input data from the various sensors, process the input data, and trigger the actuators in response to the processed input data based on an instruction or code programmed therein according to one or more routines.

[0029] As described above, leaks, e.g., leaks due to stress on the ejector or Venturi nozzle and / or deterioration in the ejector system components, such as hoses or lines, can be diagnosed and detected in the system components at or upstream of the inlets, such as inlets 144 and 142, of the ejector. The leaks can be detected, for example, at port 142 or in line 148 upstream of port 148, and leaks can be detected at port 144 or in line 150 upstream of port 144 using various sensors in the power system. However, leaks or deterioration of the components of the ejector system 141 at positions at the outlet 146 or downstream of the outlet 146, e.g., within the line 152, cannot be detected. For example, ifIf outlet 146 deteriorates due to stress and the leak detection system is performing a leak detection operation, then no leak can be detected at outlet 146. As another example, if the pipe or hose 152 becomes disconnected from outlet 146 or deteriorates, then the system may not be able to detect that a leak is occurring.

[0030] To reduce unwanted emissions, the shut-off valve 214, which couples the outlet 146 to the LES 173, is configured to interrupt at least part of the fuel vapor venting operation when deterioration at the shut-off valve is detected. For example, deterioration of a venting line can be indicated based on a reading of current through the shut-off valve. If the shut-off valve is disconnected from the LES 173, or at least partially disconnected, or if the current through the shut-off valve changes unexpectedly, the shut-off valve can close to interrupt the operation of the venting system. For example, corrective actions can be taken in response to a detected disconnection at the shut-off valve, such as...The draining operation can be stopped, the shut-off valve 214 can be closed, and / or an on-board diagnostic system can be notified of a fault in the draining system so that maintenance can be carried out.

[0031] Fig. Figure 2 shows another exemplary vehicle system 100, which includes an ejector system 141. In Fig. 2 correspond to the same numbers in Fig. 1. The same elements shown above. Fig. Figure 2 shows an exemplary ejector system that includes a shut-off valve 214 integrated with the ejector 140, such that the shut-off valve 214 is directly coupled to the drive outlet 146 of the ejector 140. The shut-off valve 214 can form part of the housing 168 of the ejector 140, so that the ejector 140 and the shut-off valve 214 are formed together in a single component. As another example, the shut-off valve 214 can be rigidly coupled to the outlet 146 by welding or by a mechanical coupling. As above with reference to Fig. As described in Figure 1, the shut-off valve 214, which couples the outlet 146 to the LES 173, is configured to interrupt at least part of the fuel vapor discharge operation when deterioration is detected at the shut-off valve.

[0032] In this example, the drive outlet 146 of the ejector 140 is directly coupled to the inlet line 118 via the shut-off valve at a point upstream of the compressor 126, between the compressor 126 and the air filter 172. In this way, a hose or line, such as the one in Fig. The line 152 shown in Figure 1 is eliminated from the ejector system. Furthermore, the rigid coupling of the outlet 146 to the inlet line 118 via the shut-off valve 214 can cause the loads on the ejector 140 to leak at the shut-off valve, so that remedial measures can be taken in response to current through the shut-off valve, as described below with reference to Fig. 3 described.

[0033] Fig. Figure 3 shows an example procedure 300 for a two-way emptying system, such as a two-way emptying system 171, which is located in the Fig. 1 and Fig.Figure 2 shows that in Method 300, an ejector system, such as ejector system 141, can be used during supercharged engine operation to discharge fuel vapor from a canister into the engine inlet. Furthermore, in some examples, leaks can be diagnosed at locations in the ejector system upstream of the ejector outlet, and corrective actions can be taken in response to a detected leak. As another example, corrective actions can be taken if a separation or other deterioration is identified at the shut-off valve coupled to the air inlet system, such as shut-off valve 214 coupled to air inlet system 173.

[0034] In the case of 302, procedure 300 includes determining whether a drain request has occurred. For example, a fuel vapor drain event can be initiated in response to a quantity of fuel vapor stored in the fuel vapor canister exceeding a threshold quantity. Furthermore, draining can be initiated when a start-up temperature of an exhaust aftertreatment device has been reached. If a drain request has occurred, a drain event can be initiated, whereby the controller 12 can set the duty cycle of the CPV solenoid 202 and open the CPV 158. The pressures within the fuel vapor drain system 200 can then draw fresh air through the vent 136, the fuel vapor canister 104, and the CPV 158, allowing the fuel vapors to flow into the line 150.

[0035] In response to a discharge initiation at 302, procedure 300 continues to 304. At 304, procedure 300 includes determining whether supercharged engine operation is present. The supercharge conditions may include the conditions during which the compressor is operating. The supercharge conditions may include, for example, a high engine load condition and / or a super-atmospheric inlet condition, where the inlet manifold pressure is greater than atmospheric pressure by a threshold amount.

[0036] If, as described in section 304, the engine is not operating with supercharging, then vacuum conditions may be present, with the procedure continuing from section 300 to 308. These vacuum conditions may include the vacuum conditions of the intake manifold. The vacuum conditions of the intake manifold may, for example, be present during an idling condition of the engine, with the manifold pressure being a threshold value below atmospheric pressure.

[0037] In procedure 300, part of method 308 involves supplying fuel vapor to the inlet downstream of the compressor. The vacuum in the inlet system 23 can, for example, draw fuel vapor from the canister through lines 150 and 151 into the inlet manifold 116.

[0038] However, if the operating conditions of the supercharged engine are present at 304, then procedure 300 continues to 310. At 310, procedure 300 involves directing the air through the ejector. For example, fresh air can be directed from the air filter 174 into the intake port 118. During the supercharging conditions, the compressor 126 pressurizes the air in the intake port 118, so that the intake manifold pressure is positive. The pressure in the intake port 118 upstream of the compressor 126 is lower than the intake manifold pressure during the operation of the compressor 126, and this pressure differential causes fluid to flow from the intake port 118 through the port 148 and via the ejector inlet 142 into the ejector 140. This fluid can, for example, contain a mixture of air and fuel.After the fluid has flowed into the ejector via the port 142, it flows through the converging opening 212 in the nozzle 204 in one direction from the port 142 to the outlet 146.

[0039] In procedure 300, part 312 involves drawing fuel vapor from the canister into the ejector. Because the nozzle diameter gradually decreases in one direction of this flow, a low-pressure zone is created, for example, in a region of the opening 212 adjacent to the suction inlet 144. The pressure in this low-pressure zone is lower than the pressure in line 150. When this pressure differential is present, it provides a vacuum in line 150 to draw fuel vapor from the canister 104. This pressure differential can further cause a flow of fuel vapor from the fuel vapor canister through the CPV and into port 144 of the ejector 140.

[0040] In the case of 314, the method 300 involves supplying fuel vapor to the inlet upstream of the compressor. Upon entering the ejector, the fuel vapors, for example, can be drawn together with the fluid from the inlet manifold out of the ejector via the outlet port 146 and into the inlet 118 in a position upstream of the compressor 126. The operation of the compressor 126 then draws the fluid and the fuel vapors from the ejector 140 into the inlet port 118 and through the compressor. After the fluid and the fuel vapors have been compressed by the compressor 126, they flow through the charge air cooler 156 for supply via the throttle valve 114 to the inlet manifold 116.

[0041] In 316, procedure 300 includes determining whether the entry conditions for leak testing are met. For example, procedure 300 can assess whether to perform a diagnostic leak test after a threshold period between leak tests has elapsed. In another example, a diagnostic leak test of the ejector system can be performed if the vacuum generated by the ejector system is not produced at a set rate. As another example, a shut-off valve coupled to the air intake system, such as shut-off valve 214, can be monitored to determine whether a separation occurs at the shut-off valve. For example, shut-off valve 214 can be configured to close in response to a leak occurring at the valve, which is detected by one or more sensors in the air intake system 173 and / or sensors in the shut-off valve.As another example, the shut-off valve may contain mechanical features configured to close the valve in response to an indication of current through the shut-off valve.

[0042] If the entry conditions for leak testing at 416 are met, procedure 300 proceeds to 318. At 318, procedure 300 may optionally include diagnosing leaks upstream of the ejector orifice in some examples. In one example, the compressor is operated at a constant speed while the throttle position is constant and the engine speed is constant. If less than a set pressure develops downstream of the compressor, it can be determined that there is a leak upstream of the ejector orifice. In some examples, further conditions, such as the pressure downstream of the compressor being less than a threshold value and the vacuum being supplied by the ejector system at less than a threshold rate, may be the conditions for determining a component leak upstream of the ejector orifice.

[0043] In the 320 procedure, 300 can optionally include the diagnosis of leaks upstream of a low-pressure section of the ejector. In one example, a valve is opened to initiate the flow of a moving fluid through the ejector. The moving fluid can be air, which may be compressed via a turbocharger. All vacuum consumers can be commanded to a closed state, and the pressure within the components upstream of the ejector's low-pressure section can be sampled by one or more pressure sensors. Air is drawn from the components upstream of the ejector's low-pressure section to the ejector, assuming a limited leak exists. The moving fluid, along with the air, is returned to the engine at a location upstream of the compressor at a point in the ejector's low-pressure section.If less than a threshold amount of negative pressure develops in the components upstream of the low-pressure region of the ejector, it can be determined that there is a leak in one or more components upstream of the low-pressure region of the ejector.

[0044] In 321, the procedure 300 includes determining whether a separation from the air inlet system (LES) exists. For example, the shut-off valve 214 coupled to the air inlet system 173 can be monitored to determine whether a separation or leak exists at or near an interface between the shut-off valve and the air inlet system. For example, the shut-off valve 214 can include one or more airflow sensors to detect changes in flow through the shut-off valve. If the flow rate through the shut-off valve falls below a threshold value under drain conditions, then a separation can be detected, and corrective action can be taken, e.g., the shut-off valve can close.

[0045] In 322, procedure 300 includes determining whether a leak is detected. As described above, for example, in some examples, leaks from the ejector located upstream of the converging orifice and the low-pressure region of the ejector can be diagnosed or detected. In other examples, leaks at the shut-off valve 214 can be detected, for example, if the hose 152 deteriorates or becomes disconnected, or if the connection between the shut-off valve 214 and the LES 173 is compromised.

[0046] If a leak is detected at 322, procedure 300 continues to 324. At 324, procedure 300 includes closing the shut-off valve to interrupt the flow through the ejector. For example, if a leak is detected at or upstream of the ejector inlets 142 and 144, then a shut-off valve, such as shut-off valve 214, can be set to interrupt the flow through the converging orifice of the ejector and into the engine inlet upstream of the compressor.

[0047] In particular, diagnostics use the shut-off valve in the high-pressure drain line to indicate a lack of flow through the drain line.

[0048] A leak or separation in the discharge line is inferred based on the absence of flow. This absence of flow may indicate a separation between the shut-off valve and the engine inlet. In response to a separation between the shut-off valve and the engine inlet, the shut-off valve can be closed to interrupt airflow from the engine inlet downstream of the compressor through the converging orifice in the ejector.

[0049] To reduce unwanted emissions, the shut-off valve 214, which couples the outlet 146 to the LES 173, is configured, for example, to interrupt at least part of the fuel vapor venting operation if deterioration at the shut-off valve is detected. If the shut-off valve is decoupled from the LES 173 or at least partially disconnected from it, or if the current through the shut-off valve changes unexpectedly, then the shut-off valve can close to interrupt the operation of the venting system.

[0050] In procedure 300, 326 includes the indication of deterioration. For example, if a leak is detected at 318, 320, or 321, procedure 300 can provide the operator with a notification to have the engine serviced. For example, corrective actions can be taken in response to a detected disconnection at the shut-off valve. This could include stopping the drain operation, closing the shut-off valve 214, and / or notifying an on-board diagnostic system of a fault in the drain system so that maintenance can be performed. Furthermore, procedure 300 can store the leak information in memory and set a diagnostic code to alert an operator to take corrective action. For example, a no-drain flow signal can be sent to the electronic control module (ECM) with a deterioration code.

Claims

[1] Multi-way discharge system for a power machine (112) comprising the following: an ejector (140) which includes a restriction, a first (142) and a second inlet (144) and an outlet (146); and a shut-off valve (214) which is fixedly attached to an inlet (23) of the power machine (112) and coupled to the outlet (146), wherein the shut-off valve (214) is configured to close in response to a separation of the shut-off valve (214) from the inlet (23) of the power machine (112). [2] System according to claim 1, wherein the shut-off valve (214) is coupled to the outlet (146) via a hose (152). [3] System according to claim 1, wherein the shut-off valve (214) is integrated with the ejector (140). [4] System according to claim 1, wherein the shut-off valve (214) is configured to close in response to a leak upstream of the outlet (146). [5] System according to claim 1, wherein the shut-off valve (214) is coupled upstream of a compressor (126) to the inlet (23) of the power machine (112), wherein the inlet (23) of the power machine (112) includes a main inlet channel (118) for admitting air entering the power machine (112), wherein the inlet (23) of the power machine (112) is made of a plastic pipe. [6] System according to claim 1, wherein the restriction converges from the first inlet (142) to the second inlet (144). [7] System according to claim 1, wherein the first inlet (142) is coupled to the inlet (23) of the engine (112) between a throttle valve (114) and a compressor (126) of the engine (112) and the second inlet (144) is coupled to a fuel vapor canister (104). [8] System according to claim 7, wherein the second inlet (144) is coupled to the canister (104) via a line (150), wherein the line (150) contains a canister drain valve (158) arranged therein, and wherein the line (150) is coupled to the inlet (23) of the engine (112) downstream of the throttle valve (114) at a location in the line (151) between the canister drain valve (158) and the second inlet (144).

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